(TiB2) is intentionally added to the melt for grain refinement to improve mechanical properties. Phosphorus is added to the melt hypereutectic alloys for modification of the silicon phase for better mechanical properties. This creates AlP inclusions. Boron treatment inclusions ( (Ti, V)B2 ) form when boron is added to the melt to increase conductivity by precipitating vanadium and titanium. Less frequently found inclusions The following inclusion types can also be found in aluminium alloys: alumina needles (Al2O3), nitrides (AlN), iron oxides (FeO), manganese oxides (MnO), fluorides (Na3AlF6, NaF, CaF2, …), aluminium borides (AlB2, AlB12), borocarbides (Al4C4B). Bone ash (Ca3(PO4)2) sometimes added to patch cracks in the trough can be found as inclusions in the melt. Inclusion measurement Several methods exist to measure the inclusion content in liquid aluminium. The most common methods are PoDFA, Prefil, K-Mold and LiMCA. Measuring the inclusions is of great help to understand the impact of furnace preparation, alloying practice, feedstock mix, settling time, and similar parameters on melt cleanliness. PoDFA The PoDFA method provides information on the composition and concentration of the inclusions in molten aluminum. PoDFA is widely used for process characterization and optimization, as well as product improvement. It allows to quickly and accurately assess the effects of various operating practices on metal cleanliness or identify filtration efficiency. The PoDFA method was developed by Rio Tinto Alcan in the 70s. The metallographic analysis method has been optimized for over the years on a wide variety of alloys. The measurement principle is the following: A predetermined quantity of liquid aluminum is filtered under controlled conditions using a very fine porosity filter. Inclusions in the melt are concentrated at the filter surface by a factor of about 10,000. The filter, along with the residual metal, is then cut, mounted and polished before being analyzed under an optical microscope by a trained PoDFA metallographer. Prefil The Prefil method is similar to PoDFA but, in addition to the metallographic analysis, Prefil provides also an immediate feedback on metal cleanliness from the metal flowrate through the filter. Because everything about the filtration is well controlled (pressure, metal temperature, ...), the only parameter affecting the filtration speed is the inclusion content. One can determine the cleanliness level from the filtration curve (weight of metal filtered as a function of time). K-Mold K-Mold is a fracture test method. Liquid metal is cast into a mold containing notches. Once solidified, the